Error Identification

It should be ‘he enjoyed reading’. It refers to a habit that has resulted because of that infirmity. ‘Enjoyed to read’ suggests immediacy of time, which is an error. It is now a trait, which is best stated by ‘he enjoyed reading’.
No error

The sentence opens in past tense and the same tense is maintained in (B) and (C), but not in (D). It should be ‘she wanted his help’. It is important that there is no mismatch of tense in one sentence. So, the whole sentence should read as: She hesitated (past) to contact him as she did not want (past) him to think (though in the present tense, it is here to complete the action suggested by ‘did not want’) she wanted his help.

It should be 'the deal' since a specific deal will have to be cancelled. It should be ‘cancel the deal’. Therefore, the error is in D.

The entire statement is in indirect speech, except this part. ‘That do not take any further step in the matter’ should be rephrased as ‘not to take any further step in the matter’. Direct or indirect speeches also refer to tense. If a sentence has begun in a direct narrative form, the same form must be carried forward to avoid any mismatch. The material part of the sentence is ‘the Chief Minister asked the official not to take any further action in the matter’. This material part is contained in (A) and (C). In (B) 'who had not prepared the draft' is a qualifying clause that qualifies the noun ‘official’.

There is no error

This is a conditional statement. This kind of statement is used when we talk about something generally not expected to occur or is purely imaginary. Here, the mother says that I could have achieved success (this means I have not achieved success) if (this is the condition) I had not wasted my time and energy on trifling matters (means I have wasted my time and energy on trifling matters). The sentence is perfectly in order.

There is no error
There is no error
There is no error
It should be 'the temperature of this room is as high as that of the other room'. In the example above, temperature is compared with the other room when it is temperature of the other room that is to be compared. Temperature has to be compared with temperature, and when we say 'is as high as that of…' this 'that of' means 'temperature of'. Instead of repeating noun 'that of' is used as pronoun.
There is no error

There is no error.
It is planning to, not planning for. Here too, the situation is identical. I am planning to do something and that something is ‘to compile’ a book on grammar. It is wrong to say ‘I am planning for compiling’.
There is no error
There is no error
There is no error

There is no error
‘at competition’ is wrong. It should be ‘to compete’ as it suggests action which is the requirement here. ‘At’ suggests object, but in this sentence the object is in C) segment and the qualifier in D) segment. In A) ‘She’ is the subject while the rest of the sentence is part of the predicate and when ‘aim’ is used to suggest action, we say ‘aim to do something’ as in the present case. So, ‘she aims to compete for…’
There is no error
There is no error
There is no error

'For all good men' not 'man'

There is no error
There is no error
‘do not chirp’. A sentence has at least one subject and one predicate. Subject of the main clause is ‘the chirping birds’, so the predicate of the main clause should accord with this and it should accordingly be ‘do not chirp’. If the main subject clause and the main predicate clause are put together, they should read as ‘the chirping birds do not chirp in mirth’. Other clauses are mere embellishments. There are no errors in the rest of the parts.
There is no error

“One of’ means ‘one out of so many or one out of several’. So, it should be ‘one of my scholar brothers’.
There is no error
There is no error
There is no error
There is no error

(A) 'One of the great attributes (one out of many attributes) is…' The mistake has therefore occurred in A) and B) C) and D) are free from errors.
There is no error
There is no error
There is no error
There is no error

'No sooner did the whistle blow' is the correct expression because it gives substance to what follows. What follows is a flurry of activities forcing passengers to make a dash for their seats. 'Whistle blew' does not convey the sense of immediacy and urgency. It blew, but we do not seem to know when.
This part signifies the immediacy of the situation.
Use of “amongst” is correct
This refers to the result of the flurry of activities.
There is no error

The subject is 'the priest' and not 'not the priest'. Also, it distorts what we call apposition in grammar. Did 'not the priest' seems to be leading you to something when what we are entitled to know is what exactly the priest said. So, the right way of saying it would be 'did the priest not tell you to recite the mantra a number of times?'
This sentence is in the present tense and this part follows the tense.
This sentence is in the present tense and this part follows the tense
This means to recite the mantra several times.
There is no error

This follows the format of neither-nor and uses “the” as a particular minister is being referred.
This uses the right pronoun (it can also be “her”)
'neither the minister nor his personal secretary was found on the scene'. Both the minister and his personal secretary are referred to as two distinct individuals separately. In a nutshell, it means 'the minister was not found on the scene' and 'the personal secretary was not found on the scene'. When combined together, the first second subject determines whether the verb will be singular or plural.
Correct use of preposition.
There is no error

This part refers to an event in the past, the sentence is in simple past tense. No error found.
Commanders-in-chief. Even though chiefs is often used, it would be improper and incorrect to say commander-in-chiefs. When commanders are present, there is no need for chiefs.
The tense matches the opening part of the sentence. Hence, no error found.
No error found
No error

The opening part of the sentence is in simple present tense. No error found.
“these” supports the present tense of the opening statement.
No error found in this part.
It should be 'superior to' and not superior than. This is a prepositional error. 'To' is the only preposition the word takes. Mistakes are usually made because 'superior' is often treated as conventional comparative form of super. It stands on its own as an independent adjective.
No error

All that we can do' is the subject and there is no error in this part.
”beggers” acts as the complement of the subject. There is also no error in this part.
All that we can do' is the subject and is quantified as singular. Its verb that occurs in C must also be singular. As the subject has 'beggars' as its complement, an error is made by putting 'are' after beggars (plural). Error therefore occurs in C. 'Are' needs to be replaced by 'is'.
This completes the sentence, no error found.
There is no error found

There is no error found.
Seema and her niece 'were' (not was) taking two different routes. Seema and her niece are two individuals put together as compound subject. The verb must be in agreement with the subject, i.e. it should be in plural.
There is no error found.
There is no error found
There is no error

show the statement in the past indefinite and no error is found.
is a continuation of A and agrees with it.
A and B show the statement in past indefinite whereas C) puts it in present perfect. This is a case of tense mismatch. It should read as 'after retiring from active service, he chose to…'
A correct part of sentence which follows the meaning.
No error found

'Left to myself' means given a choice and it is perfectly in order.
This is a sentence in future tense. There is no error found
The mistake occurs in C. 'Prefer' takes only 'to' as preposition. So, it should read as “I will always prefer reciting Eliot to reciting Wilfred Owen.” Reciting Eliot and reciting Owen are two independent activities.
This denotes an activity and there is no error found.
There is no error

This means “out of regard” or “respecting” her wishes. It is a correct use of the word and there is no error found.
This is a simple sentence in past tense. There is no error found.
We introduce people “to” each other. There is no error found.
Mistake occurs in D. It should be 'who is a singer and musician'. Here, the reference is to the same individual. There is therefore, no need for article against the second noun when two nouns are joined by 'and' in the given example.
There is no error

There is no error found
There is no error found
Mistake occurs in C. 'None' means 'no one' and is definitely singular even though these days there is a tendency to use 'none' both as singular and plural depending on the sense conveyed by it.  Grammatically to be on the right side, we must use 'none' as singular unless warranted otherwise by the sense of the sentences.
There is no error found
There is no error

Mistake occurs in A. No subject has been provided. It should therefore begin as 'she, being a mellifluous singer….' A sentence must have a subject. Where subject is not given, it has to be supplied.
The plural “all” is followed the plural “friends”. No error found.
This refers to “wanted her to attend” No error found.
“On” is used for day and dates.
No error found

This part implies an action to be taken.
This part refers to the reason why the action is needed
This action is supposed to be taken.
It should be 'until he has understood the finer elements'. Until means 'till not' or 'not till'. It has the negative element already. Therefore, 'until he has not understood…'vitiates the meaning of the writer.
No error found